1. Field of the Invention
The present invention relates to an image recording apparatus for recording an image on a recording medium.
Image recording apparatuses include a printer, an electronic printer, a facsimile machine, and a copying machine.
2. Related Background Art
A conventional image recording apparatus known as a printer and an electronic typewriter is available wherein a recording head is mounted on a carriage which is reciprocated along a platen in a printing direction. The recording head is moved in synchronism with movement of the carriage and forms an image consisting of a dot matrix on a recording sheet on the basis of printing data. When one-line recording is completed, the recording sheet is fed by a one-line pitch, and recording of the next line is then performed. When one-page recording is completed, the recording sheet is fed and exhausted.
In a conventional thermal recording apparatus, recording is performed while a thermal head is moved in tight contact with a sheet. The recording apparatus of this type includes a thermal head up/down mechanism.
In another conventional thermal transfer recording apparatus, an ink ribbon cassette can be replaceably mounted on a carriage. During recording (in the head-down state), the ink ribbon is fed to the front surface of a recording head at a velocity corresponding to a carriage moving velocity.
In this conventional image recording apparatus, an up/down operation of a thermal head and feeding of a recording sheet are performed by a single motor.
In each of these image recording apparatuses, it is difficult to switch from a printing function to a recording sheet feed function during printing. Only when the thermal head is located at its home position (e.g., the left end position), the mode can be switched to the sheet feed function, thus requiring a long mode switching time.
In still another conventional image recording apparatus of this type, carriage movement and a take-up operation of the ink ribbon (or an ink sheet) is performed by a single motor.
With this arrangement, a gear for transmitting a drive force of the motor to an ink ribbon take-up shaft is disposed in a displacement member which is coaxial with the take-up shaft.
With the above arrangement, extra parts such as a gear must be used to align a carriage moving direction with a ribbon take-up direction.